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1.
Molecules ; 26(5)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800794

RESUMO

Pesticides are widely used in agriculture to increase and protect crop production. A substantial percentage of the active substances applied is retained in the soil or flows into water courses, constituting a very relevant environmental problem. There are several methods for the removal of pesticides from soils and water; however, their efficiency is still a challenge. An alternative to current methods relies on the use of effective adsorbents in removing pesticides which are, simultaneously, capable of releasing pesticides into the soil when needed. This reduces costs related to their application and waste treatments and, thus, overall environmental costs. In this paper, we describe the synthesis and preparation of activated carbon-containing poly(ß-cyclodextrin) composites. The composites were characterized by different techniques and their ability to absorb pesticides was assessed by using two active substances: cymoxanil and imidacloprid. Composites with 5 and 10 wt% of activated carbon showed very good stability, high removal efficiencies (>75%) and pesticide sorption capacity up to ca. 50 mg g-1. The effect of additives (NaCl and urea) was also evaluated. The composites were able to release around 30% of the initial sorbed amount of pesticide without losing the capacity to keep the maximum removal efficiency in sorption/desorption cycles.


Assuntos
Carvão Vegetal/química , Géis/química , Praguicidas/análise , Praguicidas/isolamento & purificação , Propilenoglicóis/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , beta-Ciclodextrinas/química
2.
Ann Dermatol Venereol ; 145(3): 166-172, 2018 Mar.
Artigo em Francês | MEDLINE | ID: mdl-29229192

RESUMO

BACKGROUND: The aim of this study was to describe special features of patients with systemic sclerosis (SSc) diagnosed after the age of 70. PATIENTS AND METHODS: This is a retrospective study of patients aged above 70 years at the time of diagnosis of SSc and followed at an internal medicine unit between 2000 and 2015. Co-morbidities and clinical characteristics were analyzed, as well as survival at 1, 2 and 3 years. RESULTS: Of 246 patients, 27 (11%) were included (89% women, 96% Caucasians, age 78.3±4.5 years). Synchronous cancer was noted in 3 patients. SSc was mostly limited cutaneous only (24/27), with telangiectasia (63%), gastroesophageal reflux (59%) and digital ulcers (22%), and was associated with anti-centromere antibody (69%). Interstitial lung disease was not frequent (29%). Pulmonary arterial hypertension (PAH) was suspected at diagnosis of SSc in 14 cases (52%), but only 5 patients had undergone heart catheterization, with severe PAH in 3 cases. Survival at 1 and 3 years was 85.2% and 66.7%, and was worse in the case of suspected PAH, at 78.6% and 57.1% respectively. CONCLUSION: Cases of SSc diagnosed after 70 years are mostly limited cutaneous forms. Suspicion of PAH is frequent, and PAH may be the main initial sign of the disease for patients at this age. There may be association with synchronous cancer. Survival is poor.


Assuntos
Medicina Interna , Transtornos de Início Tardio/diagnóstico , Escleroderma Sistêmico/diagnóstico , Neoplasias Cutâneas/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , França/epidemiologia , Refluxo Gastroesofágico/complicações , Humanos , Transtornos de Início Tardio/mortalidade , Doenças Pulmonares Intersticiais/complicações , Masculino , Estudos Retrospectivos , Fatores de Risco , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/mortalidade , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/mortalidade , Úlcera Cutânea/complicações , Telangiectasia/complicações
3.
Ann Hematol ; 96(6): 943-950, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28374163

RESUMO

The DHAP regimen (high-dose cytarabine in combination with dexamethasone and cisplatin) with or without rituximab (DHAP+/-R) is one of the most common regimens in daily practice. It is considered the standard treatment for relapse or refractory Hodgkin's and non-Hodgkin's lymphoma (NHL). Cisplatin nephrotoxicity is a major concern, and other platinum compounds are being tried. We performed a monocentric retrospective analysis to evaluate the use of carboplatin, so-called DHAC+/-R regimen. The purpose was to assess the toxicity of the DHAC+/-R regimen in real-life. The Dexamethasone, Cytarabine, Carboplatin (DHAC) regimen consisted of carboplatin AUC = 5 mg/ml/min (targeted area under the curve with Calvert's formula) on day 1, cytarabine 2 g/m2 twice a day on day 2 and IV dexamethasone 40 mg from days 1 to 4. Rituximab was administrated at 375 mg/m2 on day 1 for CD20+ NHL. The interval between courses was 21 days. During the period considered, 199 patients received DHAC+/-R. For the entire cohort, median follow-up is 24 months (range, 2-82), median OS is not reached (NR), estimated 2-year OS is 75% (95% CI, 69-83) and median progression-free survival (PFS) is 46 months (95% CI, 22-NA). Of 144 patients scheduled for autologous stem cell transplantation (ASCT), 102 (71%, NA = 2) were in response after DHAC+/-R and all except 4 underwent ASCT. Grade ≥ 3 haematological toxicities were mainly thrombocytopenia (n = 101) and anaemia (n = 95). Grade ≥ 3 neutropenia occurred in 10 patients. No grade ≥ 3 renal and one grade 3 neurological toxicity were reported. DHAC+/-R is feasible in daily practice, provides good response rates and jeopardises neither stem cell collection nor ASCT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Adolescente , Adulto , Idoso , Anemia/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Cisplatino/administração & dosagem , Terapia Combinada , Citarabina/administração & dosagem , Dexametasona/administração & dosagem , Intervalo Livre de Doença , Doença de Hodgkin/terapia , Humanos , Linfoma não Hodgkin/terapia , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Indução de Remissão , Estudos Retrospectivos , Rituximab/administração & dosagem , Transplante de Células-Tronco/métodos , Trombocitopenia/induzido quimicamente , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
4.
J Synchrotron Radiat ; 23(1): 353-68, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26698085

RESUMO

The European Synchrotron Radiation Facility has recently made available to the user community a facility totally dedicated to Time-resolved and Extreme-conditions X-ray Absorption Spectroscopy--TEXAS. Based on an upgrade of the former energy-dispersive XAS beamline ID24, it provides a unique experimental tool combining unprecedented brilliance (up to 10(14) photons s(-1) on a 4 µm × 4 µm FWHM spot) and detection speed for a full EXAFS spectrum (100 ps per spectrum). The science mission includes studies of processes down to the nanosecond timescale, and investigations of matter at extreme pressure (500 GPa), temperature (10000 K) and magnetic field (30 T). The core activities of the beamline are centered on new experiments dedicated to the investigation of extreme states of matter that can be maintained only for very short periods of time. Here the infrastructure, optical scheme, detection systems and sample environments used to enable the mission-critical performance are described, and examples of first results on the investigation of the electronic and local structure in melts at pressure and temperature conditions relevant to the Earth's interior and in laser-shocked matter are given.

5.
J Synchrotron Radiat ; 22(6): 1548-54, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26524321

RESUMO

BM23 is the general-purpose EXAFS bending-magnet beamline at the ESRF, replacing the former BM29 beamline in the framework of the ESRF upgrade. Its mission is to serve the whole XAS user community by providing access to a basic service in addition to the many specialized instruments available at the ESRF. BM23 offers high signal-to-noise ratio EXAFS in a large energy range (5-75 keV), continuous energy scanning for quick-EXAFS on the second timescale and a micro-XAS station delivering a spot size of 4 µm × 4 µm FWHM. It is a user-friendly facility featuring a high degree of automation, online EXAFS data reduction and a flexible sample environment.

6.
Semin Cancer Biol ; 31: 106-10, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24972142

RESUMO

One in eight women in the United States will be diagnosed with invasive breast cancer in her lifetime. Advances in therapeutic strategies, diagnosis, and improved awareness have resulted in a significant reduction in breast cancer related mortality. However, there is a continued need for more effective and less toxic drugs for both the prevention and the treatment of breast cancer in order to see a continued decline in the morbidity and mortality associated with this disease. Recent studies suggest that the cGMP signaling pathway may be aberrantly regulated in breast cancer. As such, this pathway may serve as a source of novel targets for future breast cancer drug discovery efforts. This review provides an overview of cGMP signaling in normal physiology and in breast cancer as well as current strategies being investigated for targeting this pathway in breast cancer.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/prevenção & controle , GMP Cíclico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Feminino , Guanosina Trifosfato/metabolismo , Guanilato Ciclase/metabolismo , Humanos , Modelos Biológicos
7.
Orthop Traumatol Surg Res ; 99(5): 607-13, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23911134

RESUMO

INTRODUCTION: Ninety percent of the lesions resulting from diving injuries affect the cervical spine and are potentially associated with spinal cord injuries. The objective is to determine the most frequent lesion mechanisms. Evaluate the therapeutic alternatives and the biomechanical evolution (kyphotic deformation) of diving-induced cervical spine injuries. Define epidemiological characteristics of diving injuries. MATERIALS AND METHODS: A retrospective analysis over a period of 10 years was undertaken for patients admitted to the Department of Neurosurgery of Montpellier, France, with cervical spinal injuries due to a diving accident. Patients were re-evaluated and clinical and radiological evaluation follow-ups were done. RESULTS: This study included 64 patients. Cervical spine injuries resulting from diving predominantly affect young male subjects. They represent 9.5% of all the cervical spine injuries. In 22% of cases, patients presented severe neurological troubles (ASIA A, B, C) at the time of admission. A surgical treatment was done in 85% of cases, mostly using an anterior cervical approach. DISCUSSION: This is a retrospective study (type IV) with some limitations. The incidence of diving injuries in our region is one of the highest as compared to reports in the literature. Despite an increase of our surgical indications, 55% of these cases end up with a residual kyphotic deformation but there is no relationship between the severity of late vertebral deformity and high Neck Pain and Disability Scale (NPDS) scores. LEVEL OF EVIDENCE: Level IV, retrospective study.


Assuntos
Vértebras Cervicais/lesões , Mergulho/lesões , Fixação de Fratura/métodos , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/cirurgia , Adolescente , Adulto , Fatores Etários , Transplante Ósseo/métodos , Estudos de Coortes , Descompressão Cirúrgica/métodos , Feminino , Seguimentos , Fixação de Fratura/efeitos adversos , Consolidação da Fratura/fisiologia , França , Humanos , Escala de Gravidade do Ferimento , Imageamento por Ressonância Magnética/métodos , Masculino , Dor Pós-Operatória/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Medição de Risco , Fraturas da Coluna Vertebral/diagnóstico , Fusão Vertebral/métodos , Traumatismos da Coluna Vertebral/etiologia , Traumatismos da Coluna Vertebral/fisiopatologia , Traumatismos da Coluna Vertebral/cirurgia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
8.
Cell Death Dis ; 2: e218, 2011 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-21993394

RESUMO

Serotonergic innervation of the spinal cord in mammals has multiple roles in the control of motor, sensory and visceral functions. In rats, functional consequences of spinal cord injury at thoracic level can be improved by a substitutive transplantation of serotonin (5-HT) neurons or regeneration under the trophic influence of grafted stem cells. Translation to either pharmacological and/or cellular therapies in humans requires the mapping of the spinal cord 5-HT innervation and its receptors to determine their involvement in specific functions. Here, we have performed a preliminary mapping of serotonergic processes and serotonin-lA (5-HT(1A)) receptors in thoracic and lumbar segments of the human spinal cord. As in rodents and non-human primates, 5-HT profiles in human spinal cord are present in the ventral horn, surrounding motoneurons, and also contact their presumptive dendrites at lumbar level. 5-HT(1A) receptors are present in the same area, but are more densely expressed at lumbar level. 5-HT profiles are also present in the intermediolateral region, where 5-HT(1A) receptors are absent. Finally, we observed numerous serotonergic profiles in the superficial part (equivalent of Rexed lamina II) of the dorsal horn, which also displayed high levels of 5-HT(1A) receptors. These findings pave the way for local specific therapies involving cellular and/or pharmacological tools targeting the serotonergic system.


Assuntos
Receptor 5-HT1A de Serotonina/metabolismo , Neurônios Serotoninérgicos/citologia , Medula Espinal/anatomia & histologia , Adolescente , Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ratos , Neurônios Serotoninérgicos/metabolismo , Medula Espinal/metabolismo , Adulto Jovem
9.
Ann Phys Rehabil Med ; 52(4): 330-51, 2009 May.
Artigo em Inglês, Francês | MEDLINE | ID: mdl-19886026

RESUMO

INTRODUCTION: Thanks to the Internet, we can now have access to more information about spinal cord repair. Spinal cord injured (SCI) patients request more information and hospitals offer specific spinal cord repair medical consultations. OBJECTIVE: Provide practical and relevant elements to physicians and other healthcare professionals involved in the care of SCI patients in order to provide adequate answers to their questions. METHOD: Our literature review was based on English and French publications indexed in PubMed and the main Internet websites dedicated to spinal cord repair. RESULTS: A wide array of research possibilities including notions of anatomy, physiology, biology, anatomopathology and spinal cord imaging is available for the global care of the SCI patient. Prevention and repair strategies (regeneration, transplant, stem cells, gene therapy, biomaterials, using sublesional uninjured spinal tissue, electrical stimulation, brain/computer interface, etc.) for the injured spinal cord are under development. It is necessary to detail the studies conducted and define the limits of these new strategies and benchmark them to the realistic medical and rehabilitation care available to these patients. CONCLUSION: Research is quickly progressing and clinical trials will be developed in the near future. They will have to answer to strict methodological and ethical guidelines. They will first be designed for a small number of patients. The results will probably be fragmented and progress will be made through different successive steps.


Assuntos
Procedimentos Ortopédicos/métodos , Traumatismos da Medula Espinal/terapia , Humanos , Regeneração Nervosa/efeitos dos fármacos , Regeneração Nervosa/fisiologia , Medula Espinal/anatomia & histologia , Medula Espinal/cirurgia , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/prevenção & controle
10.
J Neurosci Res ; 86(9): 1916-26, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18335522

RESUMO

Adult human and rodent brains contain neural stem and progenitor cells, and the presence of neural stem cells in the adult rodent spinal cord has also been described. Here, using electron microscopy, expression of neural precursor cell markers, and cell culture, we investigated whether neural precursor cells are also present in adult human spinal cord. In well-preserved nonpathological post-mortem human adult spinal cord, nestin, Sox2, GFAP, CD15, Nkx6.1, and PSA-NCAM were found to be expressed heterogeneously by cells located around the central canal. Ultrastructural analysis revealed the existence of immature cells close to the ependymal cells, which display characteristics of type B and C cells found in the adult rodent brain subventricular region, which are considered to be stem and progenitor cells, respectively. Completely dissociated spinal cord cells reproducibly formed Sox2(+) nestin(+) neurospheres containing proliferative precursor cells. On differentiation, these generate glial cells and gamma-aminobutyric acid (GABA)-ergic neurons. These results provide the first evidence for the existence in the adult human spinal cord of neural precursors with the potential to differentiate into neurons and glia. They represent a major interest for endogenous regeneration of spinal cord after trauma and in degenerative diseases.


Assuntos
Neuroglia/citologia , Neurônios/citologia , Medula Espinal/citologia , Medula Espinal/fisiologia , Células-Tronco/citologia , Adulto , Animais , Biomarcadores/metabolismo , Morte Encefálica , Técnicas de Cultura de Células , Diferenciação Celular , Humanos , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Neuroglia/fisiologia , Neurônios/fisiologia , Células-Tronco/fisiologia , Doadores de Tecidos
12.
Neuron ; 30(3): 707-23, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11430805

RESUMO

Dorsal root ganglion neurons project axons to specific target layers in the gray matter of the spinal cord, according to their sensory modality. Using an in vivo approach, we demonstrate an involvement of the two immunoglobulin superfamily cell adhesion molecules axonin-1/TAG-1 and F11/F3/contactin in subpopulation-specific sensory axon guidance. Proprioceptive neurons, which establish connections with motoneurons in the ventral horn, depend on F11 interactions. Nociceptive fibers, which target to layers in the dorsal horn, require axonin-1 for pathfinding. In vitro NgCAM and NrCAM were shown to bind to both axonin-1 and F11. However, despite this fact and despite their ubiquitous expression in the spinal cord, NgCAM and NrCAM are selective binding partners for axonin-1 and F11 in sensory axon guidance. Whereas nociceptive pathfinding depends on NgCAM and axonin-1, proprioceptive fibers require NrCAM and F11.


Assuntos
Células do Corno Anterior/citologia , Moléculas de Adesão Celular Neuronais/metabolismo , Gânglios Espinais/citologia , Moléculas de Adesão de Célula Nervosa/metabolismo , Neurônios Aferentes/citologia , Medula Espinal/citologia , Animais , Células do Corno Anterior/metabolismo , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular Neurônio-Glia/metabolismo , Embrião de Galinha , Contactina 2 , Contactinas , Gânglios Espinais/embriologia , Neurônios Aferentes/metabolismo , Nociceptores/citologia , Propriocepção/fisiologia , Ligação Proteica/fisiologia , Receptor trkA/metabolismo , Medula Espinal/embriologia
13.
Crit Care Med ; 11(8): 591-7, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6409503

RESUMO

Fifteen patients with adult respiratory distress syndrome (ARDS) were studied: 11 in the early stage of ARDS (group 1); 4 in the late stage (group 2). The inspiratory and expiratory static pressure-volume (P-V) curves of the respiratory system were compared to the pulmonary shunt (Qsp/Qt) when PEEP was increased; cardiac output was kept constant. In group 1 patients, we found that a concavity on the P-V curves was associated with an abrupt decrease in Qsp/Qt when PEEP was increased; the concavity on the expiratory curve was correlated with the change in Qsp/Qt but not the concavity on the inspiratory curve. In group 2 patients, the P-V curves were found rectilinear and Qsp/Qt was not abruptly decreased when PEEP was increased. Expiratory P-V curve can be used to determine: first, whether a patient should be ventilated with PEEP; second, the PEEP level which can be set on the respirator. In group 1 patients, when PEEP was set to a value corresponding to the inflexion point, i.e., the point of departure from the exponential shape (mean value 14.6 +/- 2.8 cm H2O), Qsp/Qt compared to zero PEEP was abruptly decreased to 87.6 +/- 6%; further increase in PEEP had little advantage.


Assuntos
Ventilação com Pressão Positiva Intermitente , Respiração com Pressão Positiva , Troca Gasosa Pulmonar , Síndrome do Desconforto Respiratório/fisiopatologia , Adolescente , Adulto , Idoso , Dióxido de Carbono/sangue , Criança , Feminino , Capacidade Residual Funcional , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Pressão , Edema Pulmonar/fisiopatologia , Fibrose Pulmonar/fisiopatologia , Síndrome do Desconforto Respiratório/terapia
14.
J Virol ; 38(1): 82-90, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6264116

RESUMO

Simian virus 40 transcriptional complexes could be extracted from CV1 cells late in infection and separated from the bulk of inactive viral chromatin. Sucrose gradient sedimentation, cesium sulfate equilibrium density gradient centrifugation, and electron microscopy indicated that the viral transcriptional complexes corresponded to at least 0.5 to 1% of the viral minichromosomes extracted, about 5,000 copies per cell.


Assuntos
RNA Viral/biossíntese , Vírus 40 dos Símios/genética , Transcrição Gênica , Replicação Viral , Células Cultivadas , Centrifugação com Gradiente de Concentração , Cromossomos/fisiologia , Cromossomos/ultraestrutura , DNA Viral/genética , Microscopia Eletrônica , Fatores de Tempo
15.
Proc Natl Acad Sci U S A ; 77(11): 6511-5, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6935664

RESUMO

Double-stranded cDNA was synthesized from a mouse liver mRNA fraction enriched for metallothionein mRNA activity, ligated to restriction site linkers, inserted into pBR322, and used to transform Escherichia coli chi 1776. The sequence of the largest plasmid containing DNA that hybridized to metallothionein mRNA was determined and shown to contain a 380-base-pair insert that includes the entire coding region and 3' untranslated region of metallothionein-I. The metallothionein-I insert was nick-translated and used to screen both a mouse myeloma and a mouse embryo DNA library in bacteriophage lambda. A metallothionein-I genomic clone containing 13-15 kilobase pairs of mouse DNA was isolated from each library. Both contain a 3.8-kilobase-pair EcoRI fragment that hybridizes to the metallothionein-I probe. The location, size, and orientation of the metallothionein-I gene within the 3.8-kilobase-pair fragment were determined by heteroduplex and restriction mapping. The gene spans 1.1 kilobase pairs and contains at least two introns.


Assuntos
Genes , Metaloproteínas/genética , Metalotioneína/genética , RNA Mensageiro/genética , Animais , DNA Recombinante , Fígado/fisiologia , Camundongos , Plasmídeos
16.
Nature ; 279(5709): 125-32, 1979 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-440416

RESUMO

Two large DNA fragments overlapping the chicken ovalbumin gene have been isolated by molecular cloning. Analysis of these fragments provided a map of a 46,000-base pair region of the chicken genome. This region contains the complete ovalbumin gene (including its mRNA leader-coding sequence) and at least two other genes of unknown function. All three genes are orientated in the same direction and their expression in chicken oviduct is under hormonal control. The three genes share some sequence homologies, suggesting that duplications have occurred in the ovalbumin gene region in the course of evolution.


Assuntos
Estrogênios/farmacologia , Genes , Ligação Genética , Ovalbumina/genética , Animais , Sequência de Bases , Galinhas , DNA Recombinante , Feminino , Peso Molecular , Hibridização de Ácido Nucleico , Oviductos , Transcrição Gênica/efeitos dos fármacos
17.
Cell ; 14(3): 629-39, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-688385

RESUMO

The Eco RI fragment "b" of chicken DNA (Breathnach, Mandel and Chambon, 1977), which contains the sequences coding for the 5' quarter of ovalbumin mRNA (ov mRNA), has been isolated by molecular cloning using a "shotgun" approach. Electron microscopy and restriction enzyme analysis have revealed that the sequences coding for the 5' quarter (approximately 500 nucleotides) of ov mRNA are split into four regions separated by three intervening sequences. The cloning procedure seems to be reliable, since the restriction enzyme pattern of the cloned Econ RI fragment "b" is similar to that of the corresponding chromosomal DNA fragment. There is no evidence supporting the existence of a 150-200 nucleotide long sequence at the 5' end of the ov mRNA similar to the "leader" sequences found at the 5' end of some adenovirus and SV40 mRNAs.


Assuntos
Genes , Ovalbumina/genética , RNA Mensageiro/genética , Animais , Sequência de Bases , Galinhas , Enzimas de Restrição do DNA , DNA Recombinante , Microscopia Eletrônica , Hibridização de Ácido Nucleico
18.
J Virol ; 26(2): 364-79, 1978 May.
Artigo em Inglês | MEDLINE | ID: mdl-207893

RESUMO

Deoxyribonucleoprotein complexes released 17 h postinfection from adenovirus type 1 (Ad2)-infected HeLa cell nuclei were shown by electron microscopy to contain filaments much thicker (about 200 A [20 nm]) than double-stranded DNA (about 20 A [2 nm]). The complexes were partially purified through a linear sucrose gradient, concentrated, and further purified in a metrizamide gradient. The major protein present in the complexes was identified as the 72,000-dalton (72K), adenovirus-coded single-stranded DNA-binding protein (72K DBP). Three types of complexes have been visualized by electron microscopy. Some linear complexes were uniformly thick, and their length corresponded roughly to that of the adenovirus genome. Other linear genome-length complexes appeared to consist of a thick filament connected to a thinner filament with the diameter of double-stranded DNA. Forked complexes consisting of one thick filament connected to a genome-length, thinner double-stranded DNA filament were also visualized. Both thick and thin filaments were sensitive to DNase and not to RNase, but only the thick filaments were digested by the single-strand-specific Neurospora crassa nuclease, indicating that they correspond to a complex of 72K DBP and Ad2 single-stranded DNA. Experiments with anti-72K DBP immunoglobulins indicated that these nucleoprotein complexes, containing the 72K DBP, correspond to replicative intermediates. Both strands of the Ad2 genome were found associated to the 72K DBP. Altogether, our results establish the in vivo association of the 72K DBP with adenovirus single-stranded DNA, as previously suggested from in vitro studies, and support a strand displacement mechanism for Ad2 DNA replication, in which both strands can be displaced. In addition, our results indicate that, late in infection, histones are not bound to adenovirus DNA in the form of a nucleosomal chromatine-like structure.


Assuntos
Adenovírus Humanos , DNA Helicases/metabolismo , Replicação do DNA , DNA Viral/metabolismo , Proteínas Virais/metabolismo , Replicação Viral , Desoxirribonucleoproteínas/análise , Células HeLa , Microscopia Eletrônica
19.
J Clin Endocrinol Metab ; 44(2): 413-9, 1977 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-190257

RESUMO

Protein kinase activity has been studied in four human adrenocortical tumors and compared to the one of the normal human adrenal. In two cases where the lack of action of ACTH was related to an anomaly of ACTH receptor, the protein kinase activity was normal. In the other two cases the ACTH receptor was normal, but the protein kinase activity was different from that of the normal adrenal. In one of these cases where the steroidogenesis response of isolated tumor cells to ACTH and DcAMP was higher than in normal adrenal, basal and cAMP stimulated protein kinase activities were significantly higher than those of the normal adrenal, but the activation constants of both nucleotides were similar to those of the normal gland. In the other case, the basal and the cAMP stimulated protein kinase activities were significantly lower, as well as the activation constant of cAMP. However, the binding affinity of 3H-cAMP was normal. Normal adrenal cytosol contains three protein kinases, as resolved by DEAE-cellulose, two of which designated I and II, are cAMP-dependent. The DEAE-cellulose chromatography of the last tumor showed a loss of isoenzyme II. In addition, the protein kinase eluted at the same molarity as that of isoenzyme I of the normal adrenal was not activated by cAMP. Therefore, the lack of response to ACTH of some adrenocortical human tumors may be attributed either to an anomaly of the ACTH receptor or to some defect of the cAMP-dependent protein kinase.


Assuntos
Neoplasias do Córtex Suprarrenal/enzimologia , Neoplasias das Glândulas Suprarrenais/enzimologia , AMP Cíclico/farmacologia , Proteínas Quinases/metabolismo , GMP Cíclico/farmacologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Cinética , Protamina Quinase/metabolismo , Protaminas , Proteínas Quinases/isolamento & purificação
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